Patent document JP 2012-249410A discloses one example of a conventional in-vehicle control system.
In the patent document, an electric power charger is used at a charging facility, a charging device is mounted in an electric vehicle and a charging cable is provided for connecting the charger and the charging device. The charger includes a charging circuit, a control circuit, a first communication circuit and the like. The charging device includes a battery 10, a second communication circuit, a control data setting circuit and the like. The charging cable includes therein a power cable and a communication cable. The power cable supplies a charging current outputted from the charging circuit to the battery 10. The communication cable communicates between the first communication circuit and the second communication circuit. This charging cable not only connects electrically the charging circuit and the battery 10 but also connects the first communication circuit and the second communication circuit to enable mutual communication therebetween.
Each of plural electronic devices generally communicates each other by way of a differential voltage method, which uses a double-wire type communication line having two terminal circuits. When the charging facility communicates with one of the plural electronic devices through the communication line, the communication cable in the charging cable is connected to the communication line. A connection of the communication cable to the communication line forms a network, in which at least one of the plural electronic devices is connected to the charger to be communicable mutually through the communication line. The charging facility preferably includes a terminal circuit to maintain quality of communication in a case of communication with one of the plural electronic devices through the communication line.
However, this network results in having three terminal circuits in a case of connection of the charging facility with the communication cable and tends to lower quality of communication between the charging facility and the electronic device or between the electronic devices.